Flight booking tips

Booking a Flight the Frugal Way - interesting article with some good websites mentioned, but really does illustrate just how much time "do it yourself" can take. A commenter in Venice says that 2 low cost euro carriers have stopped their flights or are out of business - not sure which ones though. I wish there was a Kayak or Orbitz type site that searched all the cheap euro airlines - that I have not seen yet. Would be very useful.